Neighbors' daughter is from out of town. While visiting in late spring 2021, and while her kids and our neighbors were freshly jabbed, my daughter spent the day over there playing with the kids and spent the next few days with fever/sniffles. Could have been any number of bugs, but it sure makes one wonder. For a LONG time that was our only instance of a sniffle in the house. None of the rest of us got it, whatever it was.
Those symptoms came about as a result of their immune systems gearing up to fight the spike proteins the vaxxed there were shedding.